Coulomb battery meters and induction stoves

[arcot]

Coulomb battery meter (calibrated correctly to 100 percent on lithium 6 Kw battery bank) reads resistant heater and all other devices correctly
BUT
misleads 300 watts off inverter to 6 Amp draw much lower than realistic draw down.

Pulsing of the induction ccooktop seems to give false readings on the meter.

 

[sarabande]

Two thoughts:-

Inverter is producing clipped sine output.

Many Induction cookers produce lower ranges of heat by averaging the full heat in pulses over time.

I have a 10 inch Tefal induction plate, and can hear the system switching on and off at low power selection.

 

[B27]

I bought a cheap DC volt/current/power/Ah/Wh meter from ebay.
It's handy but only for 'steady' loads.
I think it samples once a second or so?

The cure might be to filter the current sensor signal, maybe with a resistor-capacitor network.

 

[geem]

I use one of these. Lithium batteries. 3kw inverter and induction hob. Seems to work fine and reads the low output of the pulsing induction hob on power settings below 1000w